The prior art is replete with apparatus for driving wheelchairs and bicycles. Examples of such apparatus are disclosed in U.S. Pat. Nos. 4,865,344; 4,762,332; 4,652,026; 4,453,729; 4,274,651; 4,117,915; 4,063,747; 3,994,509; 3,877,725; 3,666,292; 3,309,110; 1,273,693 and 494,839. However, there is little art known to the present inventor for driving the crankshaft or drive shaft of motor vehicles, except for that presently used in conventional piston and rotary driven engines. What little art is known is as follows: U.S. Pat. Nos. 5,076,379; 5,025,756; 5,016,580; 4,573,369 and 4,556,141.
A review of the above patents reveals that none of the apparatus disclosed therein is capable of efficiently converting linear motion to rotary motion for the purpose of driving a shaft, axle and the like. Most of the apparatus disclosed in the patents require that the operator move a handle or pedal through some sort of an arcuate or curved path in order to make a power stroke with a device. For example, in U.S. Pat. No. 3,877,725 to Barroza, it can be seen in FIG. 4 that the wheelchair is driven by moving handle 3 through the arcuate path illustrated by the arrows in FIG. 4. Similarly, in U.S. Pat. No. 4,063,747 to Young, it can be seen in FIG. 1 that the bicycle disclosed therein is powered by moving pedals 36 through an arcuate path. It will also be appreciated that the pedal of a conventional bicycle also follows an arcuate path as it revolves about the axis of the bicycle's main sprocket.
One problem with generating power along a curved or arcuate path is that the portion of the path over which maximum power can be generated is very short. For example, in a conventional bicycle, maximum power is generated during that portion of the pedal's path which travels from about +45.degree. from the horizontal about -30.degree. from the horizontal. As can be visualized, it is difficult to generate significant power outside this portion of the pedal's path since the operator's foot is simply not at an angle with respect to the pedal which enables the generation of much power. The connecting rod/crankshaft attached to the piston of an internal combustion engine suffers from the same problem since the mechanics of the combination are no different than that provided by the bicyclist's leg/pedal combination.